Liquid purification methods and apparatus

ABSTRACT

Liquid purification methods and apparatus are disclosed. An example apparatus includes a frame to define an interior space, the frame having an inner surface in contact with air of the interior space; a barrier positioned between a body of liquid and the interior space; and an absorber suspended from the frame to transfer liquid from the body of liquid into the interior space via an opening in the barrier.

FIELD OF THE DISCLOSURE

This disclosure relates generally to treatment of liquids and, moreparticularly, to liquid purification methods and apparatus.

BACKGROUND

Purification of liquids typically involves removal of impurities. Forexample, salt water is desalinated to provide potable water.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a purification and collectionapparatus constructed in accordance with teachings of this disclosure.

FIG. 2 is a block diagram of an example implementation of a controllerfor the example purification and collection apparatus of FIG. 1.

FIG. 3 is flowchart representative of machine readable instructions thatmay be executed to implement the example controller of FIG. 2.

FIG. 4 is a block diagram of an example processing system implementingthe controller of FIGS. 1 and/or 2 by executing the example machinereadable instructions of FIG. 3.

The figures are not to scale. Instead, to clarify multiple layers andregions, the thickness of the layers may be enlarged in the drawings.Wherever possible, the same reference numbers will be used throughoutthe drawing(s) and accompanying written description to refer to the sameor like parts. As used in this patent, stating that any part (e.g., alayer, film, area, or plate) is in any way positioned on (e.g.,positioned on, located on, disposed on, or formed on, etc.) anotherpart, means that the referenced part is either in contact with the otherpart, or that the referenced part is above the other part with one ormore intermediate part(s) located therebetween. Stating that any part isin contact with another part means that there is no intermediate partbetween the two parts.

DETAILED DESCRIPTION

Providing and/or obtaining sufficient amounts of fresh water in certainregions, environments, and/or economies presents challenges. Shortagesof fresh water result from, for example, climate, increasingpopulations, pollution, and technologies that allow people to live inarid regions. Desalination is an example process that may alleviate suchshortages. Desalination plants convert salt water to fresh water byremoving salt from the salt water. However, desalination plants arecostly to build and operate due to, for example, external energy sourcerequirements (e.g., burning of fossil fuels for heating and/or coolingparts of the process), the need to deliver the salt water to thedesalination plants, maintenance, labor, etc. In many instances,especially in the depressed economies in which fresh water shortagesoften exist, the costs of desalination plants preclude implementation,especially at large-scale production levels.

Example liquid purification methods and apparatus disclosed hereinprovide low cost, low maintenance, and highly sustainable purificationand collection of liquids relative to known desalination plants. Asdisclosed in detail below in connection with FIGS. 1-4, examplesdisclosed herein rely on solar radiation, rather than fossil fuels, toheat an interior space defined by a structure or frame. Examplesdisclosed herein place non-purified liquid, such as salt water of a seaor ocean, within the interior space. Unlike known systems that deliverynon-purified liquids to a desalination plant, sometimes over greatdistances, example structures disclosed herein float on a source of thenon-purified liquid. Thus, examples disclosed herein do not requirecostly delivery of non-purified liquids. As the interior space providedby examples disclosed herein is heated, the non-purified liquidevaporates. Examples disclosed herein include one or more condensationcollection surfaces that are cooler than the interior space. Thecondensation collection surfaces of examples disclosed herein are influid communication with one or more collection reservoirs such that thecondensation, having been purified of salt via the evaporation andcondensation processes, is stored separately from the non-purifiedsource of liquid.

Notably, examples disclosed herein reduce or eliminate certaininefficiencies of the evaporation and condensation process. Inparticular, examples disclosed herein prevent wasteful return ofpurified liquids (e.g., water with the salt having been removed) to anon-purified source (e.g., a saline body of water) from which thepurified liquids were extracted. For instance, examples disclosed hereinrecognize that a portion of the humid air in the heated interior spacemay condense on a surface of the source of non-purified liquid ratherthan condensing on the condensation collection surfaces. To prevent thisinefficiency, examples disclosed herein employ one or more insulationbathers between the non-purified source of liquid and the interior spacethat is heated via solar radiation. The insulation barrier(s) ofexamples disclosed herein retain more heat than the surface of thenon-purified liquid (e.g., the surface of the saline body of water). Asa result, the temperature of the insulation barrier(s) is more similarto the temperature of the interior space than the surface of thenon-purified liquid. Accordingly, much less (if any) condensation occurson the insulation barrier(s) of examples disclosed herein relative tothe cooler surface of the non-purified source of liquid. Depending onconditions, little or no condensation may occur on the insulationbarrier(s) of examples disclosed herein. As a result, a higherpercentage of the possible condensation occurs on the collectionsurfaces, thereby leading to more efficient collection of the purifiedliquid.

Moreover, examples disclosed herein enable use of the insulationbarrier(s) that separate the non-purified source of liquid from theheated interior space. Examples disclosed herein employ one or moreabsorbers that transfer liquid into the interior space across theinsulation barrier(s). In some examples disclosed herein, the absorbersare suspended from the frame that defines the interior space such thatthe absorbers transfer liquid into the interior space beyond a topsurface of the insulation barrier(s), thereby enabling the liquid to beevaporated near the condensation collection surfaces. In some examplesdisclosed herein, a first portion of the respective absorbers issubmerged in the non-purified source, while a second portion of therespective absorbers is suspended in the interior space. The exampleabsorber(s) disclosed herein transfer the non-purified liquid from thefirst portion to the second portion via capillary action. Accordingly,the example absorbers disclosed herein positioned the non-purifiedliquid within the heated interior space and near the condensationcollection surfaces even with the insulation barrier(s) being deployed.As such, examples disclosed herein supply the non-purified liquid to theevaporation and condensation environment while benefiting from theincreased efficiencies provided by the insulation barrier(s) disclosedherein.

FIG. 1 is a diagram of an example purification structure 100 constructedin accordance with teachings of this disclosure. While the purificationstructure 100 of FIG. 1 is described below as purifying and collectingwater, the example purification structure 100 can be used to purify andcollect any suitable liquid. The example purification structure 100 ofFIG. 1 includes a frame 102 composed of non-corrosive material(s) (e.g.,corrosion-resistance metal(s) and/or plastic(s)) that is articulated orflexible to withstand wave action. The example frame 102 of FIG. 1 isdome-shaped. However, any suitable shape capable of flotation can beimplemented. In some examples, the example frame 102 of FIG. 1 has anapproximate (e.g., within a threshold) diameter of fifty (50) yards.However, the example frame 102 of FIG. 1 is scalable to any suitablesize depending on, for example, a desired output amount. The exampleframe 102 of FIG. 1 includes one or more coatings, such as Teflon, at aninterface with the body of water 104 to reduce accumulation of, forexample barnacles.

The example frame 102 of FIG. 1 is to float on a body of saline water104, such as an ocean, a sea, a lake, etc. As such, the examplepurification structure 100 is continuously provided with non-purifiedwater without devoting resources to delivery of non-purified water tothe purification structure 100. In the illustrated example of FIG. 1,the purification structure 100 is to float on the body of water 104without mooring. Alternatively, the example purification structure 100can be moored to, for example, a floor of the body of water 104. Theexample frame 102 of FIG. 1 defines an interior space 106. As solarradiation hits the example purification structure 100, the air in theinterior space 106 is heated. The trapped air in the interior space 106is heated enough to cause evaporation of water present the interiorspace 106. In the example of FIG. 1, the frame 102 is in contact withthe body of water 104, which is cooler than the air in the interiorspace 106. Accordingly, inner surfaces 108 of the frame 102 are coolerthan the air trapped in the interior space 106. As moisture of the airin the interior space 106 comes in contact with the relatively coolerinner surfaces 108 of the frame 102, the moist air condenses on theinner surfaces 108. Thus, the inner surfaces 108 are sometimes referredto herein as condensation collection surfaces 108. The examplecondensation collection surfaces 108 of FIG. 1 are pitched according tothe domed shape of the example purification structure 100 such that thecondensation formed on the condensation collection surfaces 108 runsdownhill into a collection reservoir 110. In the example of FIG. 1, thereservoir 110 is defined by the frame 102 and occupies an outerperimeter of the purification structure 100. Thus, the example reservoir110 of FIG. 1 stores water that has been desalinated via evaporation andcondensation.

As the example reservoir 110 of FIG. 1 forms the outer perimeter of theframe 102, the example reservoir 110 is in direct contact with the bodyof water 104. Accordingly, the reservoir 110 and the purified waterstored therein are cooled by the body of water 104. Because the purifiedwater within the reservoir 110 is kept relatively cool compared to theinterior space 106, the outgassing vapor pressure of the reservoir 110is lower than the outgassing vapor pressure of the interior space 106.Thus, the water within the reservoir 110 does not evaporate and/or doesnot evaporate as quickly as the water present in the interior space 106.

To further cool the reservoir 110 to ensure that the water in thereservoir 110 remains in a liquid state, outer edges 112 of the frame102 are provided with a first degree of reflectivity and a centerportion 114 of the frame 102 is provided with a second degree ofreflectivity less than the first degree of reflectivity. For example, inFIG. 1, the outer edges 112 of the frame 102 are painted white ormirrored, while the center portion 114 of the frame 102 is painted blackto ensure a temperature gradient between the air in the interior space106 and the air in the reservoir 110. Further, while wave action outsidethe perimeter of the purification structure 100 is mitigated inside theperimeter of the purification structure 100, some splashing may occur.To prevent splashing for contaminating the reservoir 110, the exampleframe 102 includes an annular lip 115.

One potential issue that may arise is condensation forming on thesurface of the body of water 104 instead of the condensation collectionsurfaces 108. To prevent condensation from occurring on the surface ofthe body water 104, the example purification structure 100 of FIG. 1includes an insulation barrier 116 positioned between the interior space106 and the body of water 104. While the example of FIG. 1 includes theinsulation barrier 116, any suitable number of insulation barriers canbe implemented. The example insulation barrier 116 of FIG. 1 abuts theexample reservoir 110 around an inner edge of the reservoir 110, therebyseparating the air of the interior space 106 from the body of water 104.

Without the example insulation barrier 116 of FIG. 1, the cool surfaceof the body of water 104 would interact with the heated, humid air ofthe interior space 106, thereby causing at least some of the moisture inthe air of the interior space 106 to condense on the surface of the bodyof water 104. The surface of the body of water 104 is cool because, forexample, the water within the purification structure 100 is constantlyflowing in and out of the purification structure 100. The condensationforming on the surface of the body of water 104 is lost fresh water and,thus, represents a waste or inefficiency of the purification process. Tomitigate or eliminate this inefficiency, the example insulation barrier116 of FIG. 1 provides a surface interacting with the air of theinterior space 106 that is warmer than the surface of the body of water104. In particular, the example barrier 116 of FIG. 1 is constructed ofheat-retaining materials such as, for example, Styrofoam® or anothermaterial having similar characteristics as Styrofoam®.

As solar radiation heats the air of the interior space 106, the solarradiation also heats the insulation barrier 116. Unlike the body ofwater 104 that is constantly flowing in and out of the purificationstructure 100, the insulation barrier 116 is fixed within thepurification structure 100 and, thus, is constantly subjected to thesame solar radiation as the interior space 106. Accordingly, thedifference in temperature between the air of the interior space 106 andthe insulation barrier 116 is less than the difference in temperaturebetween the air of the interior space 106 and the surface of the body ofwater 104 without the insulation barrier 116 in place. Thus, the exampleinsulation barrier 116 of FIG. 1 increases a percentage of the humid airof the interior space 106 that condenses on the condensation collectionsurfaces 108 and, thus, the amount of fresh water stored in thereservoir 110.

However, the separation of the body of water 104 and the interior space106 provided by the insulation barrier 116 prevents or reducesevaporation of the body of water 104. Put simply, the insulation barrier116 blocks the evaporation into the interior space 106. To enable waterfrom the body of water 104 to enter the interior space 106 with theinsulation barrier 116 in place, the example purification structure 100of FIG. 1 includes one or more absorbers 118. While the example of FIG.1 includes a plurality of absorbers 118, alternative implementationsinclude a single absorber 118. The example absorbers 118 of FIG. 8 aremounted to the example frame 102 and pass through openings in theinsulation barrier 116 to contact the body of water 104. In theillustrated example of FIG. 1, the absorbers 118 are suspended from theframe 102. The example absorbers 118 of FIG. 1 are constructed ofmaterial(s) capable of wicking liquid to transfer the liquid from onesection of the respective absorbers 118 to another section of therespective absorbers 118 via capillary action. For example, theabsorbers 118 may be constructed of cloth and/or sponge-like material.The example absorbers 118 of FIG. 1 have a wicking section 120 and anevaporation section 122. In the illustrated example, the wickingsections 120 of the absorbers 118 are positioned below the insulationbarrier 116 (e.g., in the body of water 104) and the evaporationsections 122 of the absorbers 118 are positioned above the insulationbarrier 116 (e.g., suspended in the interior space 106). As the wickingsections 120 absorb salt water from the body of water 104, the saltwater is transferred to the interior space 106 via capillary action.Thus, the example absorbers 118 of FIG. 1 carry non-purified water fromthe body of water 104 into the interior space 106, where thenon-purified water can be evaporated. Notably, the example absorbers 118of FIG. 1 are suspended from the frame 102 such that the absorbers 118wick the non-purified water away from the insulation barrier 116 andsuch that evaporation occurs closer to the condensation collectionsurfaces 108 than the insulation barrier 116. Due to the suspension ofthe absorbers 118 from the frame 102 and the resulting evaporationsection 122 of the absorbers 118 being proximate the condensationcollection surfaces 108, more evaporated water condenses on thecondensation collection surfaces 108 rather than other surfaces (e.g.,the top surface of the insulation barrier 116).

In some examples, the absorbers 118 are rigidly coupled to the frame102. Alternatively, the absorbers 118 may be movable. In the illustratedexample of FIG. 1, the absorbers 118 are coupled to the frame 102 via anactuator 124 capable of raising and lowering the absorbers 118 relativeto, for example, the frame 102. In some examples, the actuator 124collectively controls all of the absorbers 118. In some examples, theactuator 124 includes a plurality of actuators to control individualones of the absorbers 118. In the example of FIG. 1, the exampleactuator 124 controls a position of the example absorbers 118 during anevaporation mode of operation such that the wicking sections 120represent a particular percentage (e.g., twenty-five (25) percent) ofthe absorbers 118.

In the illustrated example of FIG. 1, the evaporation mode of operationcorresponds to normal operation of the purification structure 100 todesalinate the water. In some examples, the example actuator 124controls the position of the example absorbers 118 during a cleaningmode of operation such that the wicking sections 120 represent apercentage (e.g., seventy-five (75) percent) of the absorbers 118different than the percentage corresponding to the evaporation mode ofoperation.

In the illustrated example of FIG. 1, the cleaning mode of operation isentered occasionally to clear the absorbers 118 of salt and/or sedimentthat have built up on the absorbers 118 over time. That is, the exampleactuator 124 of FIG. 1 submerges a greater percentage of the absorbers118 into the body of water 104 relative to the evaporation mode ofoperation such that the sections of the absorbers 118 that are suspendedin the interior space 106 during the evaporation mode are rinsed off toremove or reduce salt and/or sediment buildup. Cleaning the absorbers118 enables more efficient transfer of water into the interior space 106via capillary action. In some examples, the actuator 124 of FIG. 1enters the cleaning mode of operation according to a schedule.Additionally or alternatively, the actuator 124 of FIG. 1 enters thecleaning mode of operation according to one or more accumulation sensors125 capable of determining an amount of salt buildup and/or sedimentbuildup on the absorbers 118. The example purification structure 100 ofFIG. 1 includes a controller 126 to operate, for example, the actuator124. An example controller 126 to facilitate the movement of theabsorbers 118 is disclosed below in connection with FIGS. 2-3. Theexample controller 126 maintains a cleaning schedule and receivessignals from the accumulation sensors 125 to control the cleaning of theabsorbers 118.

The example purification structure 100 of FIG. 1 includes one or moreattachment points 128 to enable the purification structure 100 to be,for example, towed for transport. In some examples, the reservoir 110may be emptied before transport to enable the purification structure 100to sit higher in the body of water 104. Further, after the purificationstructure 100 has been transported to a destination, the reservoir 110may be again emptied to rid the reservoir 110 of any contamination(e.g., salt water that inadvertently entered the reservoir 110 duringtransport). Additionally or alternatively, the attachment points 128 maybe used by a vessel to enable boarding of the purification structure100. In some examples, the attachment points 128 are utilized to attachmultiple instances of the purification structure 100 together to form afloating island.

The example purification structure 100 of FIG. 1 includes an extractionmechanism 130 in fluid communication with the contents of the reservoir110. The example extraction mechanism 130 of FIG. 1 includes, forexample, one or more tubes through which the contents of the reservoirmay be extracted by, for example, an extraction vessel moored to theconnection points 128. Additionally or alternatively, the extractionmechanism 130 may include tubes that extend to a collection station onshore. In the illustrated example of FIG. 1, the reservoir 110 isemptied according to a schedule. Additionally or alternatively, thereservoir 110 is emptied according to reading taken by one or more waterlevel sensors 131 deployed in connection with the reservoir 110 thatdetermine a current volume of liquid present in the reservoir 110. Asdescribed in detail below, the example controller 126 maintains anextraction schedule and receives signals from the water level sensors131 to control extraction of the contents of the reservoir.

The example purification structure 100 of FIG. 1 includes one or morelights 132. In the illustrated example, the lights 132 are solar poweredlights that utilize energy collected by one or more solar collectionpanels 134. In some examples, the solar collection panels 134additionally or alternatively supply power to the example controller126.

The example purification structure 100 of FIG. 1 may include a landingplatform for use by, for example, a helicopter. In some examples, thepurification structure 100 is wider than it is tall to provide stabilityfrom being tipped over. In the illustrated example, the purificationstructure 100 includes one or more sealed flotation tanks or pontoons136. If the example purification structure 100 of FIG. 1 is flipped overbut not sunken, the flotation tanks can be selectively flooded to sinkone edge of the purification structure 100, thereby making thepurification structure 100 float vertically. From this position, a tugcan turn the purification structure 100 to an upright position.

FIG. 2 is a block diagram representative of an example implementation ofthe example controller 126 of FIG. 1. The example controller 126 of FIG.2 controls positioning of the example absorbers 118 of FIG. 1. Theexample controller 126 of FIG. 2 includes a scheduler 200 to track oneor more schedules. In the illustrated example of FIG. 1, the scheduler200 maintains and references a cleaning schedule associated with thecleaning mode of operation for the absorbers 118. In particular, theexample absorbers 118 may accumulate salt and/or sediment over time andthe example scheduler 200 of FIG. 2 indicates times at which theabsorbers 118 are to be cleaned to reduce or eliminate the accumulatedsalt and/or sediment. In some examples, the cleaning schedule utilizedby the example scheduler 200 is configured according to one or moreenvironmental factors such as, for example, a salt concentration of theparticular body of water in which the purification structure 100 isbeing deployed, a sediment concentration of the body of water, aturbulence of the body water, and/or any other factor that maycontribute to the accumulation of salt and/or sediment on the absorbers118. In the illustrated example of FIG. 2, the example scheduler 200applies a collective cleaning schedule to all of the absorbers 118.However, the example scheduler 200 may maintain different schedules forindividual ones of the absorbers 118 when, for example, individualone(s) of the absorbers 118 have been replaced.

Additionally, the example scheduler 200 maintains and references anextraction schedule associated with the reservoir 110. In particular,the extraction schedule includes periodic dates on which the reservoir110 is scheduled for extraction. In some examples, the extractionschedule is configured based on, for example, expected production levelsof fresh water, past production levels of fresh water, and/or any othermeasurement indicative of a frequency at which the reservoir 110 shouldbe emptied.

The example controller 126 of FIG. 2 includes a sensor interpreter 202to receive and analyze signals from one or more sensors deployed on thepurification structure 100. In the illustrated example of FIG. 2, thesensor interpreter 202 receives signals from the accumulation sensors125 associated with the absorbers 118 that indicate an amount of saltand/or sediment accumulation on the absorbers 118. The example sensorinterpreter 202 of FIG. 2 determines whether a cleaning of the absorbers118 should be performed based on the signals received from theaccumulation sensors 125. For example, the sensor interpreter 202 maydetermine that the accumulation sensors 125 indicate that a thresholdamount of salt and/or sediment accumulation is present on the absorbers118. In the illustrated example of FIG. 2, the sensor interpreter 202aggregates readings from the individual accumulation sensors 125 togenerate a collective (e.g., average) accumulation indicator. In theillustrated example of FIG. 2, the example sensor interpreter 202compares the collective accumulation indicator to a collectiveaccumulation threshold to determine whether the absorbers 118 should becollectively (e.g., at a same time) cleaned. Alternatively, the sensorinterpreter 202 may compare individual readings from the individualaccumulation sensors 125 to generate individual accumulation indicators.In such examples, the sensor interpreter 202 compares the individualaccumulation indicators to individual accumulation thresholds todetermine whether the corresponding ones of the absorbers should beindividually cleaned.

Additionally, the example sensor interpreter 202 of FIG. 2 receivessignals from one or more water level sensors 131 associated with thereservoir 110 that indicate an amount of fresh water currently presentin the reservoir 110. The example sensor interpreter 202 determineswhether the reservoir 110 should be emptied based on the signalsreceived from the water level sensors 131. For example, the sensorinterpreter 202 may determine that the water level sensors indicate thata threshold amount of fresh water is currently present in the reservoir110.

When the example scheduler 200 of FIG. 2 and/or the example sensorinterpreter 202 of FIG. 2 determines that the absorbers 118 are to becleaned (e.g., individually or collectively), the example scheduler 200and/or the example sensor interpreter 202 communicate a message to anactuator interface 204. The example actuator interface 204 of FIG. 2 isin communication with the example actuator 124 of FIG. 1. When theabsorbers 118 are to be cleaned, the example actuator interface 204 ofFIG. 2 causes the actuator 124 to enter the cleaning mode of operationin which the absorbers 118 are further lowered into the body of water104 (relative to the position corresponding to the evaporation mode ofoperation). The example actuator interface 204 causes the actuator 124to leave the absorbers 118 in the lowered position for a particularduration, after which the absorbers 118 are raised back into theposition corresponding to the evaporation mode. In the illustratedexample of FIG. 2, the absorbers 118 are lowered and raisedcollectively. However, the example actuator 124 may control individualones of the actuators 118 in accordance with commands received from theactuator interface 204.

When the example scheduler 200 of FIG. 2 and/or the example sensorinterpreter 202 of FIG. 2 determines that the reservoir 110 is to beemptied, the example scheduler 200 and/or the example sensor interpreter202 communicate a message to a communicator 206. The examplecommunicator 206 of FIG. 2 is capable of communicating (e.g., via anetwork, satellite, etc.) with, for example, an extraction entity taskedwith emptying the reservoir 110 of the purification structure 100. Forexample, the communicator 206 of FIG. 2 may send a message to anextraction vessel to be deployed to the purification structure 100 whenthe reservoir 110 is full and/or scheduled for extraction. The messageconveyed by the example communicator 206 includes, for example, alocation (e.g., coordinate) of the purification structure 100 such thatthe extraction vessel can locate the purification structure 100.

While an example manner of implementing the controller of FIG. 1 isillustrated in FIG. 2, one or more of the elements, processes and/ordevices illustrated in FIG. 2 may be combined, divided, re-arranged,omitted, eliminated and/or implemented in any other way. Further, theexample scheduler 200, the example sensor interpreter 202, the exampleactuator interface 204, the example communicator 206 and/or, moregenerally, the example controller 126 of FIG. 2 may be implemented byhardware, software, firmware and/or any combination of hardware,software and/or firmware. Thus, for example, any of the examplescheduler 200, the example sensor interpreter 202, the example actuatorinterface 204, the example communicator 206 and/or, more generally, theexample controller 126 of FIG. 2 could be implemented by one or moreanalog or digital circuit(s), logic circuits, programmable processor(s),application specific integrated circuit(s) (ASIC(s)), programmable logicdevice(s) (PLD(s)) and/or field programmable logic device(s) (FPLD(s)).When reading any of the apparatus or system claims of this patent tocover a purely software and/or firmware implementation, at least one ofthe example scheduler 200, the example sensor interpreter 202, theexample actuator interface 204, the example communicator 206 and/or,more generally, the example controller 126 of FIG. 2 is/are herebyexpressly defined to include a tangible computer readable storage deviceor storage disk such as a memory, a digital versatile disk (DVD), acompact disk (CD), a Blu-ray disk, etc. storing the software and/orfirmware. Further still, the example controller 126 of FIG. 1 mayinclude one or more elements, processes and/or devices in addition to,or instead of, those illustrated in FIG. 2, and/or may include more thanone of any or all of the illustrated elements, processes and devices.

A flowchart representative of example machine readable instructions forimplementing the controller 126 of FIG. 2 is shown in FIG. 3. In thisexample, the machine readable instructions comprise a program forexecution by a processor such as the processor 412 shown in the exampleprocessor platform 400 discussed below in connection with FIG. 4. Theprogram may be embodied in software stored on a tangible computerreadable storage medium such as a CD-ROM, a floppy disk, a hard drive, adigital versatile disk (DVD), a Blu-ray disk, or a memory associatedwith the processor 412, but the entire program and/or parts thereofcould alternatively be executed by a device other than the processor 412and/or embodied in firmware or dedicated hardware. Further, although theexample program is described with reference to the flowchart illustratedin FIG. 3, many other methods of implementing the example controller 126may alternatively be used. For example, the order of execution of theblocks may be changed, and/or some of the blocks described may bechanged, eliminated, or combined.

As mentioned above, the example processes of FIG. 3 may be implementedusing coded instructions (e.g., computer and/or machine readableinstructions) stored on a tangible computer readable storage medium suchas a hard disk drive, a flash memory, a read-only memory (ROM), acompact disk (CD), a digital versatile disk (DVD), a cache, arandom-access memory (RAM) and/or any other storage device or storagedisk in which information is stored for any duration (e.g., for extendedtime periods, permanently, for brief instances, for temporarilybuffering, and/or for caching of the information). As used herein, theterm tangible computer readable storage medium is expressly defined toinclude any type of computer readable storage device and/or storage diskand to exclude propagating signals and to exclude transmission media. Asused herein, “tangible computer readable storage medium” and “tangiblemachine readable storage medium” are used interchangeably. Additionallyor alternatively, the example processes of FIG. 3 may be implementedusing coded instructions (e.g., computer and/or machine readableinstructions) stored on a non-transitory computer and/or machinereadable medium such as a hard disk drive, a flash memory, a read-onlymemory, a compact disk, a digital versatile disk, a cache, arandom-access memory and/or any other storage device or storage disk inwhich information is stored for any duration (e.g., for extended timeperiods, permanently, for brief instances, for temporarily buffering,and/or for caching of the information). As used herein, the termnon-transitory computer readable medium is expressly defined to includeany type of computer readable storage device and/or storage disk and toexclude propagating signals and to exclude transmission media. As usedherein, when the phrase “at least” is used as the transition term in apreamble of a claim, it is open-ended in the same manner as the term“comprising” is open ended.

The example of FIG. 3 begins with an initialization of the examplecontroller 126 (block 300). Initialization of the example controller 126coincides with, for example, deployment of the example purificationstructure 100 on the body of water 104. Initialization of the examplecontroller 126 includes, for example, obtaining the cleaning scheduleand/or the extraction schedule from an entity tasked with operatingand/or maintaining the example purification structure 100. In theillustrated example of FIG. 3, the example absorbers 118 are deployedwith the evaporation sections 122 suspended from the frame 102 and thewicking sections 120 submerged in the body of water 104 via the openingsin the insulation barrier 116.

In the example of FIG. 3, the scheduler 200 (FIG. 2) checks the cleaningschedule and the extraction schedule to determine whether the absorbers118 are to be cleaned and/or whether the reservoir 110 is scheduled forextraction (block 302). In the illustrated example of FIG. 3, thecleaning schedule applies to the absorbers 118 collectively. However,individual cleaning schedules may be maintained for individual ones ofthe absorbers 118 when, for example, particular ones of the absorbers118 have been replaced. If the cleaning schedule does not indicate thatthe absorbers 118 are to be cleaned (block 304), the example sensorinterpreter 202 determines whether the accumulation sensors 125 indicatethat a current amount of salt and/or sediment built up on the absorbers118 exceeds a threshold (block 306). In the illustrated example of FIG.3, readings from the accumulation sensors 125 are aggregated such thatthe absorbers 118 are treated collectively for purposes of cleaning.However, individual readings and thresholds may be applied to theindividual ones of the absorbers 118.

If the absorbers 118 are scheduled to be cleaned (e.g., collectively orindividually) (block 304) or the accumulation sensors 125 indicate thatthe accumulation threshold is exceeded (block 306) (e.g., collectivelyor individually), the example actuator interface 204 receives a messageor command from the corresponding one(s) of the scheduler 200 and thesensor interpreter 202 instructing the actuator interface 204 to enterthe cleaning mode of operation. As such, the example actuator interface204 controls the actuator 124 to lower the absorbers 118 (e.g.,collectively or individually) further into the body of water 104relative to the evaporation mode of operation (block 308). Inparticular, the actuator interface 204 instructs the actuator 124 tolower the evaporation sections 122 of the absorbers 118 into the body ofwater 104 such that the evaporation sections 122 are cleaned (e.g., saltand/or sediment is washed away from the absorbers 118) by the body ofwater 104. After the evaporation sections 122 of the absorbers 118 havebeen cleaned by the body of water 104 (e.g., placed in the body of water104 for a designated duration), the example actuator interface 204instructs the actuator 124 to position the evaporation sections 122 ofthe absorbers into the interior space 106 (block 310).

In the example of FIG. 3, the scheduler 200 determines whether theextraction schedule indicates that the reservoir 110 should be emptied(block 312). If an extraction is not scheduled (block 312), the examplesensor interpreter 202 determines whether the water level sensors 131indicate that amount of liquid in the reservoir 110 exceeds a threshold(block 314). If the either the scheduler 200 determines that theextraction schedule indicates that the reservoir 110 should be emptied(block 312) or the sensor interpreter 202 determines that the waterlevel exceeds the threshold (block 314), the example communicator 206conveys a message to, for example, an extraction vessel indicating thatthe reservoir 110 should be emptied to initiate an extraction process(block 316).

If the controller 126 is powered down (block 318), the example of FIG. 3ends (block 320). Otherwise, control returns to block 302.

FIG. 4 is a block diagram of an example processor platform 400 that hasbeen repurposed to execute the instructions of FIG. 3 to implement theexample controller 126 of FIGS. 1 and/or 2. The processor platform 400can be, for example, a microcontroller (e.g., an application specificintegrated circuit (ASIC), a programmable logic device (PLD), a fieldprogrammable logic device (FPLD)), a server, or any other type ofcomputing device. The example processor platform 400 of FIG. 4 is onethat can operate on power levels commensurate with energy collected bysolar panels and/or a combination of solar panels and backup batteries.

The processor platform 400 of the illustrated example includes aprocessor 412. The processor 412 of the illustrated example is hardware.For example, the processor 412 can be implemented by one or moreintegrated circuits, logic circuits, microprocessors or controllers fromany desired family or manufacturer. The example processor 412 of FIG. 4implements the example scheduler 200 of FIG. 2 and the example sensorinterpreter 202 of FIG. 2.

The processor 412 of the illustrated example includes a local memory 413(e.g., a cache). The processor 412 of the illustrated example is incommunication with a main memory including a volatile memory 414 and anon-volatile memory 416 via a bus 418. The volatile memory 414 may beimplemented by Synchronous Dynamic Random Access Memory (SDRAM), DynamicRandom Access Memory (DRAM), RAMBUS Dynamic Random Access Memory (RDRAM)and/or any other type of random access memory device. The non-volatilememory 416 may be implemented by flash memory and/or any other desiredtype of memory device. Access to the main memory 414, 416 is controlledby a memory controller.

The processor platform 400 of the illustrated example also includes aninterface circuit 420. The interface circuit 420 may be implemented byany type of interface standard, such as an Ethernet interface, auniversal serial bus (USB), and/or a PCI express interface.

In the illustrated example, one or more input devices 422 are connectedto the interface circuit 420. The input device(s) 422 permit(s) a userto enter data and commands into the processor 412. The input device(s)422 can be implemented by, for example, an audio sensor, a microphone, acamera (still or video), a keyboard, a button, a mouse, a touchscreen, atrack-pad, a trackball, isopoint and/or a voice recognition system.

In some examples, one or more output devices (e.g., a light emittingdiode (LED), an organic light emitting diode (OLED), a liquid crystaldisplay, a cathode ray tube display (CRT), a touchscreen, a tactileoutput device, a printer and/or speakers) may be connected to theinterface circuit 420. However, in the interest of conserving energy andoperating at low power levels due to the isolated nature of the examplepurification structure 100 of FIG. 1, the example processor platformdoes not include output devices.

The interface circuit 420 of the illustrated example includes thecommunicator 206, which may be implemented by, for example, atransmitter, a receiver, a transceiver, a modem and/or network interfacecard to facilitate exchange of data with external machines (e.g.,computing devices of any kind) via a network 426 (e.g., a wirelessEthernet connection, a cellular telephone system, etc.). The interfacecircuit 420 of the illustrated example includes the actuator interface204, which is in communication with the example actuator 124 of FIG. 1to control the actuator 124 and the corresponding absorbers 118.

In some examples, the processor platform 400 includes one or more massstorage devices (e.g., floppy disk drives, hard drive disks, compactdisk drives, Blu-ray disk drives, RAID systems, and digital versatiledisk (DVD) drives). However, in the interest of conserving energy andoperating at low power levels, the example processor platform 400 doesnot include a mass storage device.

Coded instructions 432, such as the machine readable instructions ofFIG. 3, may be stored in the volatile memory 414, the non-volatilememory 416, and/or on a removable tangible computer readable storagemedium such as a CD or DVD.

Although certain example methods, apparatus and articles of manufacturehave been disclosed herein, the scope of coverage of this patent is notlimited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe claims of this patent.

What is claimed is:
 1. An apparatus, comprising: a frame to define aninterior space, the frame having an inner surface in contact with air ofthe interior space; a barrier positioned between a body of liquid andthe interior space; an absorber suspended from the frame to transferliquid from the body of liquid into the interior space via an opening inthe barrier; and a controller to control movement of the absorber intothe body of liquid in response to an indication that the absorber is tobe cleaned.
 2. The apparatus of claim 1, wherein the barrier includesinsulation material.
 3. The apparatus of claim 1, wherein the absorberincludes: a wicking section to be placed in the body of liquid; and anevaporation section to be placed in the interior space.
 4. The apparatusof claim 3, wherein the absorber is to transfer the liquid from thewicking section to the evaporation section via capillary action.
 5. Theapparatus of claim 1, including a reservoir to store condensation formedon the inner surface of the frame.
 6. The apparatus of claim 1, whereinthe controller is to convey a message to an extraction entity inresponse to an indication that a reservoir is to be emptied, wherein thereservoir is to collect condensation from the inner surface.
 7. Theapparatus of claim 1, including a flotation structure.
 8. An apparatus,comprising: a dome-shaped frame; a reservoir defined in part by thedome-shaped frame, the reservoir to collect condensation forming on afirst surface of the dome-shaped frame; an absorber suspended from thedome-shaped frame to transfer, via capillary action, liquid from a bodyof liquid into an interior space defined by the dome-shaped frame; aninsulator to prevent condensation from forming on a surface of the bodyof liquid; and a sensor to detect an amount sediment or saltaccumulation on the absorber.
 9. The apparatus of claim 8, wherein thedome-shaped frame includes a center exterior portion and an outerexterior portion, the center exterior portion having a first degree ofreflectivity, the outer exterior portion having a second degree ofreflectivity greater than the first degree of reflectivity.
 10. Theapparatus of claim 8, including an opening in the insulator to receivethe absorber.
 11. The apparatus of claim 8, including a controller tofacilitate movement of the absorber into the body of liquid in responseto readings of the sensor.